package org.seckill.service.impl;

import org.seckill.dao.SeckillDao;
import org.seckill.dao.SuccessKilledDao;
import org.seckill.dto.Exposer;
import org.seckill.dto.SeckillExecution;
import org.seckill.entity.Seckill;
import org.seckill.entity.SuccessKilled;
import org.seckill.enums.SeckillStatEnum;
import org.seckill.exception.RepeatKillException;
import org.seckill.exception.SeckillCloseException;
import org.seckill.exception.SeckillException;
import org.seckill.service.SeckillService;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.util.DigestUtils;

import java.util.Date;
import java.util.List;

/**
 * Created by Administrator on 2017/4/1.
 */
@Service
public class SeckillServiceImpl implements SeckillService {

    private final org.slf4j.Logger logger= LoggerFactory.getLogger(this.getClass());

    //注入Service依赖
    @Autowired
    private SeckillDao seckillDao;
    @Autowired
    private SuccessKilledDao successKilledDao;
    //MD5盐值字符串，用于混淆Md5
    private final String slat="dsjkfjlkdffg56465313";

    @Override
    //TODO
    public List<Seckill> getSeckillList() {
        return seckillDao.queryAll(0,4);
    }

    @Override
    public Seckill getById(long seckillId) {
        return seckillDao.queryById(seckillId);
    }

    @Override
    public Exposer exportSeckillUrl(long seckillId) {
        Seckill seckill=seckillDao.queryById(seckillId);
        if (seckill==null){
            return new Exposer(false,seckillId);
        }
        Date startTime=seckill.getStartTime();
        Date endTime=seckill.getEndTime();
        Date nowTime=new Date();
        if (nowTime.getTime()<startTime.getTime()||nowTime.getTime()>endTime.getTime()){
            return new Exposer(false, seckillId, nowTime.getTime(), startTime.getTime(), endTime.getTime());
        }

        String md5=getMD5(seckillId);
        return new Exposer(true,md5,seckillId);
    }

    private String getMD5(long seckillId){
        String base=seckillId+"/"+slat;
        String MD5= DigestUtils.md5DigestAsHex(base.getBytes());
        return MD5;

    }

    @Override
    @Transactional
    /*
    * 使用注解控制事物方法的有点
    * 1.开发团队达成一致约定，明确注意事物方法的编程方法
    * 2.保证事务管理方法的执行时间尽可能短，不要穿插其他网络操作RPC/HTTP请求或者剥离到事务方法外部
    * 3.不是所有的方法都需要事物，如果只有一条操作，只读操作不需要事物管理控制
    * */
    public SeckillExecution executeSeckill(long seckillId, long userPhone, String md5) throws SeckillException, SeckillCloseException, RepeatKillException {
        if (md5==null||!md5.equals(getMD5(seckillId))){
            throw   new SeckillException("seckill data rewrite");
    }
        //执行秒杀逻辑 减库存+添加秒杀记录
        Date nowTime=new Date();
        try {
            int updateCount = seckillDao.reduceNumber(seckillId, nowTime);
            if (updateCount <= 0) {
                //抢购已结束
                throw new SeckillCloseException("seckill is closed");
            } else {
                //减库存成功 记录购买行为
                int insertCount = successKilledDao.insertSuccessKilled(seckillId, userPhone);
                if (insertCount <= 0) {
                    //如果重复购买
                    throw new RepeatKillException("seckill repeated");
                } else {
                    //记录抢购信息
                    SuccessKilled successKilled = successKilledDao.queryByIdWithSeckill(seckillId, userPhone);
                    //返回订单状态
                    return new SeckillExecution(seckillId, SeckillStatEnum.SUCCESS, successKilled);
                }
            }
        }catch (SeckillCloseException e1){
            throw e1;
        }catch (RepeatKillException e2){
            throw e2;
        }catch (Exception e){
            logger.error(e.getMessage(),e);
            //所有的编译器异常，转换为运行期异常
            throw new SeckillException("deckill inner error"+e.getMessage());

        }

    }


}
